A peculiar case of malignant cerebral reticulosis: clinico-pathological study

A man aged 56 years, previously healthy, developed asthenia, hypersonnia, apathy, later polydipsia and bulimia, headache and episodes of unconsciousness. There was temporary improvement with steriod therapy, but ever-deepening stupor appeared till death due to bronchopneumonia. All blood chemistry examinations were normal. The CSF IgG was elevated but no neoplastic cells were seen. At autopsy areas of grayish color in the basal gagnlia and granulomatous tissue in the floor of the third ventricle and in the mamillary bodies were seen, and the gonads were attrophied. Microscopically, in the floor of third ventricle, mamillary bodies and adjacent leptomeninges there was granulomatous tissue made up of more-or-less typical cells of the reticulum, polymorphonuclear cells, plasma cells and some phagocytes along with proliferation of small blood vessels and reticulin fibers. In addition, the white matter of the frontal lobes, pons, middle cerebellar peduncle and cerebellar white matter contained diffuse proliferation of pleomorphic histiocytic elements with questionable atypical mitoses. Notwithstanding, the morphology of our case suggests that it is a peculiar form of malignant reticulosis (or malignant histocytosis) related to histiocytosis X. The duplicity of the features of our case suggests it to be neoplastic, where the proliferative phase is followed by a granulomatous and sclerotic one.